BUG-1207: Use openflowjava-supplied MAC address utilities

The implementations provided here are trivial and do not perform as well
as they could. openflowjava has optimized versions of these, so use
those.

(cherry picked from commit c53a3bf19b81fdc927d6974017de1bcab6d841d6)
Signed-off-by: Robert Varga <robert.varga@pantheon.sk>
Signed-off-by: Michal Rehak <mirehak@cisco.com>
Change-Id: Ib9b170cbe9fab1c9702a5397bc1a786436d89ba0